Pace Neely
Science Period 8
October 3, 2013
Lab Report #1
THE DIFFUSION LAB
I. INTRODUCTION
 Purpose:
How does the temperature of water affect the diffusion rate?
 Hypothesis:
As temperature of the water increases the diffusion rate decreases, therefore the food coloring in the hot water will
diffuse faster than the food coloring in water that is room temperature and the food coloring the in the cold water will
take the longest to diffuse.
 Background Information:
Diffusion is the random thermal motion of particles. Molecules move from higher concentration to lower
concentration. The hotter the temperatures molecules are the faster they move and the faster they move the faster the
diffusion rate. The colder the temperature of the molecules the slower they move around and the slower the diffusion
rate.
II. MATERIALS and PROCEDURES
 Materials
o Hot water
o Chilled water
o Room-temperature water
o Thermometer
o Food coloring
o 3 beakers or cups
o droppers
o stop watch
 Procedures
1. Obtain samples of warm water, cold water and room-temperature water.
2. Measure the temperatures of each and record the temperatures of each water sample on the data table.
3. Label your cups of water 1-warm water, 2-chilled water and 3-room temperature water and line them up.
4. Measure out 50 ml of warm water in beaker 1,
5. Measure out 50 ml of chilled water in beaker 2.
6. Measure out 50 ml of room-temperature water in beaker 3.
7. Quickly place one drop of food coloring in each of the 3 beakers. Use your stop watch to time how long it
takes for the food coloring to diffuse (or evenly spread out) through the water. When the food coloring has
completely diffused in each beaker, record the time on your data table (but DO NOT stop the timer).
8. Record the data for all of the groups in your class. Determine the average times of diffusion for the class.
III. DATA or OBSERVATIONS
Table #1: Diffusion Rates of Different Water Temperatures
Beaker/Sample
Water
Temperature
(degrees
Celsius)
Time of
Diffusion
(seconds)
GROUP 1
Time of
Diffusion
(seconds)
GROUP 2
Time of
Diffusion
(seconds)
GROUP 3
Time of
Diffusion
(seconds)
GROUP 4
Time of
Diffusion
(seconds)
GROUP 5
Time of
Diffusion
(seconds)
GROUP 6
AVERAGE
(seconds)
#1: Warm
water
78.4
265
540
480
83
250
188
301
#2: Chilled
water
9.4
561
440
546
412
330
732
504
#3: Roomtemp water
28.8
313
594
612
285
305
640
351
Graph #1: (make a line graph of the average diffusion times for each sample. Your graph should show the water
temperatures vs. time of diffusion. Be sure to label your x axis and y axis and provide a title and a key.)
Diffusion Rates of Different Water Temperatures
IV. ANALYSIS and CONCLUSION
 Analysis
Our results showed very different diffusion rates. For the diffusion rate in warm water it took 301 seconds. For the
diffusion rate in room temperature water it took 351 seconds. Last, the diffusion rate for cold water took the longest at 504
seconds. The results showed that when the temperature was increased the diffusion rate decreased. Patterns showed that the
room temperature water always took the middle amount of time to diffuse. Some human errors include if too many drops of
food coloring were dripped into the beaker of water. Other variables that may have effected the results were the water
temperature may have changed during the experiment and the warm water could have been closer to room temperature by the
end of the experiment.
 Conclusion
The hypothesis that the food coloring in the hot water will diffuse faster than the food coloring in water that is room
temperature and the food coloring the in the cold water will take the longest to diffuse was correct.
I learned that the diffusion rate for hotter substances is faster making the making less work for the person and so this
might help us in the long run by figuring out other things about diffusion. This lab was useful because you might
need diffusion for a regular life sly like making a birthday cake, also mixing batter and adding dye.
V.
REFERENCES
Meyertholen, Edward. "Department of Biology." Austin Community College.
N.p., n.d. Web. 16 Sep 2010.
<http://www.austincc.edu/emeyerth/index.htm>.